WASHINGTON - If federal safety officials rely on their current rollover research as the basis for a vehicle rating system, they run the risk of misguiding car buyers instead of informing them.
So said Vann Wilber, director of vehicle safety for the Alliance of Automobile Manufacturers.
But the National Highway Traffic Safety Administration, in perhaps its most unequivocal statement to date, said it still plans to seek public comment this year on a program of rollover ratings. If adopted, the ratings would accompany the one-to-five-star crash-test scores.
The NHTSA statement accompanied release last week of a report on the agency's latest round of rollover research. Agency researchers ran 12 sample vehicles through hundreds of extreme maneuvers to see if reliable, repeatable tests can be found to measure rollover tendencies. They used a computerized steering device to remove the human element from the maneuvers.
Consumers Union, which petitioned NHTSA in 1996 for a rollover rating system, interpreted the report as proof that the agency is near the goal of finding the desired test or tests to rate vehicles on stability.
NHTSA will decide after fully evaluating an alternative testing method recommended by General Motors, said agency spokesman Rae Tyson.
Wilber, representing 11 manufacturers in the alliance, said people already know intuitively that 'tall, skinny things are less stable than short fat things.'
Yet, in the real world, where driver behavior is the overriding factor, Corvettes roll over more than minivans, and most rollover fatalities are high-speed, off-the-road crashes, he said.
NHTSA's tests were on a test track. Vehicles were equipped with outriggers. A Ford Ranger and Chevrolet Tracker were the two vehicles that tended to tip up on two wheels in some maneuvers.
Wilber said that a consumer information program does not have to meet the high legal standards of federal safety regulations, but he contended, 'To be reasonable it should meet some rigor or else it is disinformation.'
One surprise in the rollover testing was the number of tires that lost pressure or came loose from their rims in the extreme maneuvers. The agency is taking a closer look at those incidents, officials said.